摘要
对不同正火处理后的3.5Ni无缝钢管样品进行夏比低温冲击试验,利用金相显微镜、扫描电镜和透射电镜,观察其显微组织、断口形貌和析出组织。结果表明:随着正火冷速的增加,3.5Ni无缝钢管组织晶粒尺寸减小、形成粒状贝氏体组织,当正火冷速为25℃/s时,在细晶强化、相变强化等综合作用下,3.5Ni无缝钢管低温韧性大幅提高,冲击吸收能量(-100℃)平均值达到82 J。
Charpy impact test at low temperature of 3. 5Ni seamless steel tube was conducted after normalizing with different cooling rate.The microstructure,fracture morphology and segregation were charactered by metallographic microscope,scanning electron microscope and transmission electron microscope. The results show that with the increase of normalizing cooling rate,the grain size of 3. 5Ni seamless steel tubes decreases and granular bainite forms. When normalizing cooling rate is 25 ℃ / s,under the effect of fine grain strengthening and phase transformation strengthening,the toughness of 3. 5Ni seamless steel tube at low temperature increases obviously,the average impact absorbed energy at-100 ℃ reaches 82 J.
出处
《金属热处理》
CAS
CSCD
北大核心
2015年第7期14-19,共6页
Heat Treatment of Metals
基金
国家自然科学基金(51101113)
天津市科技发展计划项目(12ZCZDGX00600)
天津市自然基金项目(14JCYBJC16200)
关键词
3.5Ni无缝钢管
正火冷速
低温冲击韧性
3.5Ni seamless steel tube
normalizing cooling rate
low temperature impact toughness
